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Single muscle fibre analysis of carnosine and associated metabolites in Korean breath hold divers (AMA).
Author(s) -
Tallon Mark James,
Harris Roger C,
Kim Hyo J,
Kim Chang K
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.6.lb115
Subject(s) - carnosine , hypoxia (environmental) , taurine , chemistry , medicine , endocrinology , biochemistry , oxygen , amino acid , organic chemistry
Intermittent hypoxia and cold water immersion during breath‐hold diving may result in adaptations to facilitate muscle activity in these conditions. Previous work has highlighted increased carnosine ( Carn ) concentrations and enzyme activity in marine mammals exposed to hypoxic conditions. The aim of this study was to assess the adaptive responses in breath‐hold divers. Divers (n=9, 54±11y; 59±12kg) were biopsied from the v .Lateralis. Single muscle fibres were dissected and characterised as type I (T1) and II (TII). Characterised fibres were subsequently analyzed for Carn , taurine ( Tau ) (mmol.kg −1 dm), citrate synthase ( CS ) and phosphorylase ( Phos ) (μmol.g −1. min −1 @ 25 o C). Carn concentrations were higher in TI fibres (20.0±13.4) than TI (10.9±10.3) with Tau showing the opposite distribution (TI 16.3±12.1; TII 20.4±16.9). CS activities were higher in TI (39.9±11.1) than TII (30.2±12.4) fibres with Phos showing the opposite (TI 24.4±7.3;TII 39.8±10.7). CONCLUSIONS: Intermittent hypoxia experienced by divers in this study maybe insufficient to cause tissue de‐oxygenation to the extent to increase intracellular Carn in single muscle fibres compared to previously published values for untrained subjects.